Metallic compound and organic electroluminescence device comprising the same

ABSTRACT

The present invention relates to a light-emitting transition metal compound represented by the Chemical Formula 1 and Chemical Formula 2 and an organic electroluminescence device including the same. 
     In the Chemical Formulae 1 and 2, M is Ir, Pt, Rh, Re, Os, and the like, m is 2 or 3, n is 0 or 1, the sum of m and n is 3, provided that the sum of m and n is 2 when M is Pt, X, and Z are the same or different, N or P, and Y and Q are O, S, or Se, R 1  and R 5  are hydrogen, a C1 to C20 alkyl excluding an aromatic cyclic substituent, a cycloalkyl, a halogen, a linear or branched substituent including at least one halogen, or a linear or branched substituent including at least one heteroatom, and R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , R 9 , and R 10  are hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, a linear or branched substituent including at least one halogen, a linear or branched substituent including at least one heteroatom, carbonyl, vinyl, or acetylenyl, or may form a cycle, and may be the same or different.

TECHNICAL FIELD

The present invention relates to a metallic compound and an organic electroluminescence device including the same, and more particularly, to a metallic compound that is applicable as a highly efficient phosphor host material and an organic electroluminescence device including the same.

BACKGROUND OF ART

An electroluminescence device (EL device) is a self-light emitting display device having such merits as a wide viewing angle and excellent contrast as well as a quick response time.

EL devices are classified into an inorganic EL device and an organic EL device in accordance with a material used for a light emitting layer. The organic EL device has merits of improved luminance, driving voltage, response speed, and multi-colorfying property compared to an inorganic EL device.

An organic EL device is generally composed of an anode on a substrate, a hole transport layer on the anode, and a light emitting layer, an electron transport layer (ETL), and a cathode sequentially positioned thereon. The hole transport layer, light emitting layer, and electron transport layer (ETL) are organic films that are composed of organic compounds.

The organic EL device having the above structure is operated as follows.

When a voltage is applied to a space between the anode and the cathode, the holes are injected from the anode to the light emitting layer through the hole transport layer. Meanwhile, when the electrons are injected from the cathode into the light emitting layer through the electron transport layer (ETL), carriers are recombined in the region of the light emitting layer to thereby produce excitons. The state of the excitons is changed from an exited state to a base state, and the change in the state of the excitons makes the molecules of the light emitting layer emit light to thereby form an image.

Materials for forming a light emitting layer are divided into fluorescent materials using singlet excitons and phosphorescent materials using triplet excitons according to the light emitting mechanism. Phosphorescent materials generally include organic/inorganic compound structures including transition metal atoms. The transition metal atoms change triplet excitons, which used to be impossible to transition, into excitons that are possible to transition, causing them to emit phosphorescent light. Since the phosphorescent materials can use triplet excitons having a generation probability of 75%, higher luminous efficiency can be achieved than with fluorescent materials using singlet excitons having a generation probability of 25%.

Among light emitting materials using the triplet excitons are phosphorescent materials including iridium and platinum compounds (Sergey Lamansky et al. Inorg. Chem., 40,1704-1711, 2001, and Sergey Lamansky et al., J. Am. Chem. Soc., 123, 4304-4312, 2001). For blue light emitting materials, Ir compounds based on (4,6-F2ppy)₂Irpic or a fluorinated ppy ligand structure have been developed (Vladimir V. Grushin et al., Chem. Commun., 1494-1495, 2001). The (4,6-F2ppy)₂Irpic, however, has shortcomings that it emits light in a sky blue region and its large shoulder peaks increase a y value in color purity coordinates. Researchers are studying red and green light emitting materials, but there still remains great demand to develop highly efficient phosphorescent materials having a long lifespan.

DETAILED DESCRIPTION OF THE INVENTION Technical Problem

In order to solve the problems, the object of the present invention is to provide a phosphor metallic compound having a new ligand structure and an organic electroluminescence device having improved luminous efficiency and color purity.

Technical Solution

The present invention relates to a light emitting transition metal compound represented by the following Chemical Formula 1 and Chemical Formula 2 and an organic electroluminescence device including the same.

Wherein, in the above Chemical Formulae 1 and 2, M is selected from Ir, Pt, Rh, Re, Os, and the like, m is 2 or 3, n is 0 or 1, the sum of m and n is 3, provided that the sum of m and n is 2 when M is Pt,

X is an N or P atom,

Y and Q are O, S, or Se,

R¹ and R⁵ are hydrogen, a C1 to C20 alkyl excluding an aromatic cyclic substituent, a cycloalkyl, a halogen, a linear or branched substituent including at least one halogen, or a linear or branched substituent including at least one heteroatom,

R², R³, R⁴, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, a linear or branched substituent including at least one halogen, a linear or branched substituent including at least one heteroatom, carbonyl, vinyl, acetylenyl, or form a cycle, and are the same or different, and

L² is represented by the following Chemical Formulae 3, 4, and 5.

Wherein, the transition metal, M forms a complex compound by a covalent bond with a portion denoted as * in the above Chemical Formulae 3, and a coordination bond with an adjacent N or P atom,

Z and W in the above Chemical Formulae 4 and 5 are the same or different and a heteroatom of 0, N, S, or P, and

R¹¹-R²⁴ in the Chemical Formulae 3, 4, and 5 are the same or different, and are hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, a linear or branched substituent including at least one halogen, a linear or branched substituent including at least one heteroatom, carbonyl, vinyl, acetylenyl, or may form a cycle.

In the present invention, a ligand of the transition metal compound includes a benzofuro oxazole-based, benzofuro thiazole-based, benzo thio oxazole-based, benzo thio thiazole-based, naphto oxazole-based, or naphto thiazole-based derivative including a transition metal having a covalent bond with C and a coordination bond with N. In order to reduce concentration quenching, a functional group having a large steric hindrance such as an alkyl, an aryl, a halogen, a silyl, and so on is independently included in a benzo oxazole group, a benzo thiazole group, a naphto oxazole group, and a naphto thiazole group. Several nm of light-emission and light wavelength can be easily controlled in accordance with the positions of the substituents and the properties of electron donors or acceptors. The ligands are represented by the following chemical Chemical Formulae 6:

An L² ligand can change a small range of wavelength, and examples of the L² ligand are represented by any one of the following Chemical Formulae 7:

The transition metal compound represented by the above Chemical Formulae can be synthesized as follows. The following Reaction Scheme 1 shows a ligand synthesis, and Reaction Scheme 2 shows a metalation process.

As shown in Reaction Scheme 2, the metalation process is as follows: a naphto benzooxazole derivative and hydrated iridium trichloride are reacted under a nitrogen atmosphere to prepare a dimmer intermediate that includes two iridium metals sharing a Cl ligand, and then the intermediate is reacted with an auxiliary ligand in a solvent including a weak base to prepare a transition metal compound of Chemical Formula 1.

The Effect of the Invention

The phosphor material is applied to an organic electroluminescence device to increase the lifespan of a light emitting material, to increase the luminous efficiency, and to reduce concentration quenching. It can also be applied to display devices, displays, backlights, electron photographs, illumination sources, light sources, signs, signboards, interiors, and so on. It also applied to display devices, displays, backlights, electron photographs, illumination sources, light sources, signs, signboards, interiors, and so on. Compared to a conventional fluorescent organic EL device having external quantum efficiency of less than 5%, power consumption can be significantly reduced. By introducing a substituent having steric hindrance, high efficiency can be maintained even at high doping concentration, and thereby the lifespan of a device increases. The compound of the present invention can be applied for medicals purposes, and to fluorescent brighteners, photographs, UV absorbents, laser dyes, dyes for a color filter, color conversion filters, and so on.

Best Mode

The present invention can be specified by the following Examples. The Examples only illustrate the present invention and they do not limit the scope and range of the present invention, which is defined by the accompanying claims.

Example 1 Compound 1: Synthesis of (MNTZ)₂Ir(acac)

Synthesis of 2-methyl naphtothiazole (MNTZ): 5 mmol of 1-aminonaphthalene-2-thiol was added to 20 ml of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of acetic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 2-methyl naphtothiazole at a yield of 70%.

Synthesis of (MNTZ)_(2l Ir(Cl)) ₂Ir(MNTZ)₂: 5 mmol of 2-methyl naphtothiazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ at a yield of 93%.

Synthesis of (MNTZ)₂Ir(acac): 5 mmol of (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ and 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down into about 50° C. and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNTZ)₂Ir(acac) at a yield of 91%.

Example 2 Compound 2: Synthesis of (MNTZ)₂Ir(Facac)

Synthesis of (MNTZ)₂Ir(Facac): 5 mmol of (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ and 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane 100 mL and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNTZ)₂Ir(Facac) at a yield of 87%.

Example 3 Compound 3: Synthsis of (MNTZ)₂Ir(FacacF)

Synthesis of (MNTZ)₂Ir(FacacF): 5 mmol of (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ and 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 1,2-dichloroethane 100 mL, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNTZ)₂Ir(MNTZ) at a yield of 92%.

Example 4 Compound 4: Synthesis of (MNTZ)₂Ir(Pic)

Synthesis of (MNTZ)₂Ir(Pic): 5 mmol of (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNTZ)₂Ir(Pic) at a yield of 90%.

Example 5 Compound 5: Synthesis of (MNTZ)₂Ir(NPic)

Synthesis of (MNTZ)₂Ir(NPic): 5 mmol of (MNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ and 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNTZ)₂Ir(NPic) at a yield of 89%.

Example 6 Compound 6: Synthesis of (FMNTZ)₂Ir(acac)

2-trifluoromethyl naphtothiazole (FMNTZ): 5 mmol of 1-aminonaphthalene-2-thiol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of 1,1,1,5,5,5-hexafluoro acetic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 2-trifluoromethyl naphtothiazole at a yield of 71%.

Synthesis of (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂: 5 mmol of 2-trifluoromethyl naphtothiazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂ at a yield of 91%.

Synthesis of (FMNTZ)₂Ir(acac): 5 mmol of (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂ and 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down into about 50° C. and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNTZ)₂Ir(acac) at a yield of 90%.

Example 7 Compound 7: Synthesis of (FMNTZ)₂Ir(Facac)

Synthesis of (FMNTZ)₂Ir(Facac): 5 mmol of (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂ and 25 mmol of 1,5-bis trifluoromethylic anhydride, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane 100 mL and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNTZ)₂Ir(Facac) at a yield of 89%.

Example 8 Compound 8: Synthsis of (FMNTZ)₂Ir(FacacF)

Synthesis of (FMNTZ)₂Ir(FacacF): 5 mmol of (FMNTZ)₂Ir(Cl)₂Ir(MNTZ)₂ and 25 mmol of 1,1,1,5,5,5-hexafluoro-2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 1,2-dichloroethane 100 mL, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNTZ)₂Ir(FacacF) at a yield of 87%.

Example 9 Compound 9: Synthesis of (FMNTZ)₂Ir(Pic)

Synthesis of (FMNTZ)₂Ir(Pic): 5 mmol of (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂ and 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNTZ)₂Ir(Pic) at a yield of 88%.

Example 10 Compound 10: Synthesis of (FMNTZ)₂Ir(NPic)

Synthesis of (FMNTZ)₂Ir(NPic): 5 mmol of (FMNTZ)₂Ir(Cl)₂Ir(FMNTZ)₂ and 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNTZ)₂Ir(NPic) at a yiled of 88%.

Example 11 Compound 11: Synthesis of (TMSNTZ)₂Ir(acac)

Synthesis of 2-trimethylsilyl naphtothiazole (TMSNTZ): 5 mmol of 1-aminonaphthalene-2-thiol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of 1,5-bis trimethylsilylic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 2-trimethylsilyl naphtothiazole at a yield of 74%.

Synthesis of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂: 5 mmol of 2-trimethylsilyl naphtothiazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂ at a yield of 94%.

Synthesis of (TMSNTZ)₂Ir(acac): 5 mmol of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNTZ)₂Ir(acac) at a yield of 91%.

Example 12 Compound 12: Synthesis of (TMSNTZ)₂Ir(Facac)

Synthesis of (TMSNTZ)₂Ir(Facac): 5 mmol of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂ and 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNTZ)₂Ir(Facac) at a yield of 92%.

Example 13 Compound 13: Synthesis of (TMSNTZ)₂Ir(FacacF)

Synthesis of (TMSNTZ)₂Ir(FacacF): 5 mmol of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNTZ)₂Ir(FacacF) at a yield of 93%.

Example 14 Compound 14: Synthesis of (TMSNTZ)₂Ir(Pic)

Synthesis of (TMSNTZ)₂Ir(Pic): 5 mmol of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂ , 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNTZ)₂Ir(Pic) at a yield of 88%.

Example 15 Compound 15: Synthsis of (TMSNTZ)₂Ir(NPic)

Synthesis of (TMSNTZ)₂Ir(NPic): 5 mmol of (TMSNTZ)₂Ir(Cl)₂Ir(TMSNTZ)₂, 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane, and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNTZ)₂Ir(NPic) at a yield of 87%.

Example 16 Compound 16: Synthsis of (PNTTZ)₂Ir(acac)

Synthesis of phenanthro thiazole (PNTTZ): 5 mmol of 1-amino phenanthren-2-thiol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of formic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain phenanthrothiazole at a yield of 69%.

Synthesis of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂: 5 mmol of phenanthro thiazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂ at a yield of 89%.

Synthesis of (PNTTZ)₂Ir(acac): 5 mmol of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTTZ)₂Ir(acac) at a yield of 87%.

Example 17 Compound 17: Synthesis of (PNTTZ)₂Ir(Facac)

Synthesis of (PNTTZ)₂Ir(Facac): 5 mmol of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂, 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTTZ)₂Ir(Facac) at a yield of 86%.

Example 18 Compound 18: Synthesis of (PNTTZ)₂Ir(FacacF)

Synthesis of (PNTTZ)₂Ir(FacacF): 5 mmol of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTTZ)₂Ir(FacacF) at a yield of 85%.

Example 19 Compound 19: Synthesis of (PNTTZ)₂Ir(Pic)

Synthesis of (PNTTZ)₂Ir(Pic): 5 mmol of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTTZ)₂Ir(Pic) at a yield of 86%.

Example 20 Compound 20: Synthesis of (PNTTZ)₂Ir(NPic)

Synthesis of (PNTTZ)₂Ir(NPic): 5 mmol of (PNTTZ)₂Ir(Cl)₂Ir(PNTTZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTTZ)₂Ir(NPic) at a yield of 87%.

Example 21 Compound 21: Synthesis of (MNOZ)₂Ir(acac)

Synthesis of 2-methyl naphtoxazole (MNOZ): 5 mmol of 1-aminonaphthalene-2-ol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of acetic anhydride was added for 5 minutes. An acetylated product was precipitated in in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 1-aminonaphthalene-2-thiol at a yield of 73%.

Synthesis of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂: 5 mmol of 2-methyl naphtoxazole and 10 mmol of IrCl₃xH₂O were mixed in 100 mL of 2-ethoxyethanol and , and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂ at a yield of 96%.

Synthesis of (MNOZ)₂Ir(acac): 5 mmol of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNOZ)₂Ir(acac) at a yield of 88%.

Example 22 Compound 22: Synthesis of (MNOZ)₂Ir(Facac)

Synthesis of (MNOZ)₂Ir(Facac): 5 mmol of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂, 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNOZ)₂Ir(Facac) at a yield of 86%.

Example 23 Compound 23: Synthesis of (MNOZ)₂Ir(FacacF)

Synthesis of (MNOZ)₂Ir(FacacF): 5 mmol of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNOZ)₂Ir(FacacF) at a yield of 85%.

Example 24 Compound 24: Synthesis of (MNOZ)₂Ir(Pic)

Synthesis of (MNOZ)₂Ir(Pic): 5 mmol of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNOZ)₂Ir(Pic) at a yield of 86%.

Example 25 Compound 25: Synthesis of (MNOZ)₂Ir(NPic)

Synthesis of (MNOZ)₂Ir(NPic): 5 mmol of (MNOZ)₂Ir(Cl)₂Ir(MNOZ)₂, 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (MNOZ)₂Ir(NPic) at a yield of 87%.

Example 26 Compound 26: Synthesis of (FMNOZ)₂Ir(acac)

Synthesis of 2-trifluoromethyl naphtoxazole (FMNOZ): 5 mmol of 1-aminonaphthalene-2-ol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of 1,1,1,5,5,5-hexafluoro acetic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 2-trifluoromethyl naphtoxazole at a yield of 73%.

Synthesis of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂: 5 mmol of 2-trifluoromethyl naphtoxazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂ at a yield of 90%.

Synthesis of (FMNOZ)₂Ir(acac): 5 mmol of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNOZ)₂Ir(acac) at a yield of 91%.

Example 27 Compound 27: Synthesis of (FMNOZ)₂Ir(Facac)

(FMNOZ)₂Ir(Facac): 5 mmol of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)_(2,d) 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNOZ)₂Ir(Facac) at a yield of 90%.

Example 28 Compound 28: Synthesis of (FMNOZ)₂Ir(FacacF)

Synthesis of (FMNOZ)₂Ir(FacacF): 5 mmol of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNOZ)₂Ir(FacacF) at a yield of 93%.

Example 29 Compound 29: Synthesis of (FMNOZ)₂Ir(Pic)

Synthesis of (FMNOZ)₂Ir(Pic): 5 mmol of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNOZ)₂Ir(Pic) at a yield of 92%.

Example 30 Compound 30: Synthesis of (FMNOZ)₂Ir(NPic)

Synthesis of (FMNOZ)₂Ir(NPic): 5 mmol of (FMNOZ)₂Ir(Cl)₂Ir(FMNOZ)₂, 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (FMNOZ)₂Ir(NPic) at a yield of 90%.

Example 31 Compound 31: Synthesis of (TMSNOZ)₂Ir(acac)

Synthesis of 2-trimethylsilyl naphtoxazole (TMSNOZ): 5 mmol of 1-aminonaphthalene-2-ol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of 1,5-bistrimethylsilylic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain 2-trimethylsilyl naphtoxazole at a yield of 70%.

Synthesis of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂: 5 mmol of 2-trimethylsilyl naphtoxazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂ at a yield of 93%.

Synthesis of (TMSNOZ)₂Ir(acac): 5 mmol of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNOZ)₂Ir(acac) at a yield of 93%.

Example 32 Compound 32: Synthesis of (TMSNOZ)₂Ir(Facac)

(TMSNOZ)₂Ir(Facac): 5 mmol of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂, 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNOZ)₂Ir(Facac) at a yield of 90%.

Example 33 Compound 33: Synthesis of (TMSNOZ)₂Ir(FacacF)

(TMSNOZ)₂Ir(FacacF): 5 mmol of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNOZ)₂Ir(FacacF) at a yield of 89%.

Example 34 Compound 34: Synthesis of (TMSNOZ)₂Ir(Pic)

Synthesis of (TMSNOZ)₂Ir(Pic): 5 mmol of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNOZ)₂Ir(Pic) at a yield of 88%.

Example 35 Compound 35: Synthesis of (TMSNOZ)₂Ir(NPic)

Synthesis of (TMSNOZ)₂Ir(NPic): 5 mmol of (TMSNOZ)₂Ir(Cl)₂Ir(TMSNOZ)₂, 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (TMSNOZ)₂Ir(NPic) at a yield of 87%.

Example 36 Compound 36: Synthesis of (PNTOZ)₂Ir(acac)

Synthesis of phenanthro oxazole (PNTOZ): 5 mmol of 1-amino phenanthren-2-thiol was added to 20 mL of water, and 20 mg of sodium dodecylsulfate was added while agitating to obtain a uniform mixture. 7.5 mmol of formic anhydride was added for 5 minutes. A precipitation product was obtained in 5-10 minutes. The precipitation product was filtrated and rinsed with 1 ml of water twice followed by drying under vacuum. A non-precipitated reaction mixture was extracted with 25 ml of ethyl acetate twice. The separated organic layer was dried with anhydrous sodium sulfate, and a solvent was removed using a rotatary evaporator under a reduced pressure to obtain phenanthro oxazole at a yield of 71%.

Synthesis of (PNTOZ)₂Ir(Cl)21r(PNTOZ)₂: 5 mmol of phenanthro oxazole and 10 mmol of IrCl₃xH₂O were dissolved in 100 mL of 2-ethoxyethanol and refluxed for 24 hours under a nitrogen atmosphere. The solution was cooled down into room temperature, and 5% hydrochloric acid aqueous solution 200 mL was added to the solution for eduction, filtrated, rinsed with water and an ether solvent, and dried to thereby produce (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂ at a yield of 92%.

Synthesis of (PNTOZ)₂Ir(acac): 5 mmol of (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂, 25 mmol of 2,4-pentadione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTOZ)₂Ir(acac) at a yield of 94%.

Example 37 Compound 37: Synthesis of (PNTOZ)₂Ir(Facac)

Synthesis of (PNTOZ)₂Ir(Facac): 5 mmol of (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂, 25 mmol of 1,1,1-trifluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTOZ)₂Ir(Facac) at a yield of 92%.

Example 38 Compound 38: Synthesis of (PNTOZ)₂Ir(FacacF)

Synthesis of (PNTOZ)₂Ir(FacacF): 5 mmol of (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂, 25 mmol of 1,1,1,5,5,5-hexafluoropentane-2,4-dione, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTOZ)₂Ir(FacacF) at a yield of 90%.

Example 39 Compound 39: Synthesis of (PNTOZ)₂Ir(Pic)

Synthesis of (PNTOZ)₂Ir(Pic): 5 mmol of (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂, 25 mmol of picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTOZ)₂Ir(Pic) at a yield of 91%.

Example 40 Compound 40: Synthesis of (PNTOZ)₂Ir(NPic)

Synthesis of (PNTOZ)₂Ir(NPic): 5 mmol of (PNTOZ)₂Ir(Cl)₂Ir(PNTOZ)₂, 25 mmol of 5-dimethylamino picolinic acid, and 50 mmol of potassium carbonate were mixed in 100 mL of 1,2-dichloroethane and refluxed for 24 hours under a nitrogen atmosphere. After the reaction was complete, the solution was cooled down to about 50° C., and filtrated. The filtrate solution was purified by using column chromatography to thereby produce (PNTOZ)₂Ir(NPic) at a yield of 89%. PL spectra of the above chemical compounds were acquired and the results were presented in the following Table 1.

TABLE 1 Compound Yield PL (nm) Compound 1 91 562 Compound 2 87 560 Compound 3 92 559 Compound 4 90 561 Compound 5 89 558 Compound 6 90 570 Compound 7 89 569 Compound 8 87 565 Compound 9 88 567 Compound 10 88 566 Compound 11 91 562 Compound 12 92 559 Compound 13 93 556 Compound 14 88 557 Compound 15 87 552 Compound 16 87 575 Compound 17 86 572 Compound 18 85 570 Compound 19 86 573 Compound 20 87 569 Compound 21 88 552 Compound 22 86 549 Compound 23 85 545 Compound 24 86 546 Compound 25 87 545 Compound 26 91 559 Compound 27 90 556 Compound 28 93 553 Compound 29 92 555 Compound 30 90 551 Compound 31 93 549 Compound 32 90 548 Compound 33 89 544 Compound 34 88 545 Compound 35 87 542 Compound 36 94 557 Compound 37 92 553 Compound 38 90 552 Compound 39 91 554 Compound 40 89 552

Example 41

As for an anode, a 10 Ω/cm² ITO substrate produced by the Corning Company was used. A hole injection layer was formed in a thickness of 60 nm by depositing IDE406 on top of the substrate in a vacuum condition. Subsequently, a hole transport layer was formed by depositing TPD chemical compound on top of the hole injection layer in a thickness of 30 nm in a vacuum condition. A light emitting layer was formed in a thickness of 20 nm by depositing a transition metal compound on top of the hole transport layer in a vacuum condition.

Subsequently, an HBL layer was formed in a thickness of 5 nm by depositing BCP on top of the light emitting layer in a vacuum condition. An electron transport layer (ETL) was formed in a thickness of 20nm by depositing Alq3 on top of the light emitting layer in a vacuum condition. An organic electroluminescence device was completed by sequentially depositing LiF 1 nm and Al 300 nm on top of the electron transport layer in a vacuum condition to thereby form a LiF/Al electrode.

The luminance, color coordinates and efficiency of the organic electroluminescence device prepared according to Example 41 were measured.

As a result of the measurement, it can be confirmed that the organic electroluminescence device can be operated at a low voltage and implements high efficiency indicating that the metallic compound as an organic electro-luminescence material has excellent characteristics.

Simple modifications and alternations of the present invention can be easily made by the ordinary skilled person in the art within the spirit and scope of the appended claims. 

1. A metallic compound represented by the following Chemical Formula 1:

wherein M is selected from Ir, Pt, Rh, Re, and Os, m is 2 or 3, n is 0 or 1, the sum of m and n is 3, provided that the sum of m and n is 2 when M is Pt, X is N or P, Y and Q are selected from S, O, or Se, R¹ is one of hydrogen, a C1 to C20 alkyl, a cycloalkyl, a halogen, the alkyl having at least one halogen, or at least one heteroatom substituent, each of R², R³, and R⁴ is one of hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, the alkyl having at least one halogen or at least one heteroatom substituent, carbonyl, vinyl, and acetyleny, and L² is represented by the following Chemical Formulae 3, 4, and 5:

wherein, in the above formula 3, M forms a complex compound by a covalent bond with a portion denoted as *, and a coordination bond with an adjacent N or P atom, Z and W in the above Chemical Formulae 4 and 5 are the same or different and heteroatoms of O, N, S, or P, and each of R¹¹-R²⁴ in the Chemical Formulae 3, 4, and 5 is one of hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, the alkyl having at least one halogen or at least one heteroatom substituent, carbonyl, vinyl, and acetylenyl.
 2. A metallic compound represented by the following Chemical Formula 2:

wherein M is selected from Ir, Pt, Rh, Re, and Os, m is 2 or 3, n is 0 or 1, the sum of m and n is 3, provided that the sum of m and n is 2 when M is Pt, X is N or P, Y and Q are selected from S, O , or Se, R⁵ is one of hydrogen, a C1 to C20 alkyl, a cycloalkyl, a halogen, the alkyl having at least one halogen or at least one heteroatom substituent, each of R⁶, R⁷, R⁸, R⁹, and R¹⁰ is one of hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, the alkyl having at least one halogen or at least one heteroatom substituent, carbonyl, vinyl, and acetylenyl, and L² is represented by the following Chemical Formulae 3, 4, and 5:

wherein, in the above formula 3, M forms a complex compound by a covalent bond with a portion denoted as *, and a coordination bond with an adjacent N or P atom, Z and W in the above Chemical Formulae 4 and 5 are the same or different and heteroatoms of O , N, S, or P, and each of R¹¹-R²⁴ in the Chemical Formulae 3, 4, and 5 is one of hydrogen, a C1 to C20 alkyl, an aryl, a cycloalkyl, a halogen, the alkyl having at least one halogen or at least one heteroatom substituent, carbonyl, vinyl, and acetylenyl.
 3. An organic electroluminescence device comprising the light-emitting metallic compound of claim
 1. 4. An organic electroluminescence device comprising the light-emitting metallic compound of claim
 2. 